Fire Pump Wiring NEC 2002

Transcription

1 Fire Pump Wiring NEC 2002 NEC 695.3A1 Source 1 Tap Edison Edison Service Conductors NEC 695.6, or Separate Service Conductors or Underground Outside Building Transfer Switch Fire Pump Controller Fire Pump NEC 695.6B or NEC 700.9D Source 2 Generator Required City of Elmhurst Code Amendments Tab 2, Item #8 NEC Wires in conduit embedded in 2 inches concrete to transfer switch inside building NEC and NEC Wiring from Controller to Fire Pump Equipment Locations NEC All Control Wiring NEC This is not all inclusive, please consult NEC 2002, NFPA, NFC, City of Elmhurst 2004 Amendments, and ICC for additional information. Building/dubiel/firepumpwiring

2 NEC NEC NEC NEC Conductors considered outside the building. Conductors shall be considered outside of a building or other structure under any of the following conditions: 1. Where installed under not less than 50 mm (2 in.) of concrete beneath a building or other structure 2. Where installed within a building or other structure in a raceway that is encased in concrete or brick not less than 50 mm (2 in.) thick. 3. Where installed in any vault that meets the construction requirements of Article 450, Part III 4. Where installed in conduit and under not less than 450 mm (18 in.) of earth beneath a building or other structure Scope. A. Covered. This article covers the installation of the following: 1. Electric power sources and interconnecting circuits 2. Switching and control equipment dedicated to fire pump drivers B. Not Covered. This article does not cover the following: 1. The performance, maintenance, and acceptance testing of the fire pump system and the internal wiring of the components of the system 2. Pressure maintenance (jockey or makeup) pumps FPN: See NFPA , Standard for the Installation of Stationary Pumps for Fire Protection, for further information. A. Individual Sources. Where reliable, and where capable of carrying indefinitely the sum of the locked-rotor current of the fire pump motor(s) and the pressure maintenance pump motor(s) and the full-load current of the associated fire pump accessory equipment when connected to this power supply, the power source for an electric motor-driven fire pump shall be one or more of the following. 1. Electric Utility Service Connection. A fire pump shall be permitted to be supplied by a separate service, or by a tap located ahead of and not within the same cabinet, enclosure, or vertical switchboard section as the service disconnecting means. The connection shall be located and arranged so as to minimize the possibility of damage by fire from within the premises and from exposing hazards. A tap ahead of the service disconnecting means shall comply with 23082(4). The service equipment shall comply with the labeling requirements in and the location requirements in (B). 2. On-Site Power Production Facility. A fire pump shall be permitted to be supplied by an on-site power production facility. The source facility shall be located and protected to minimize the possibility of damage by fire. [NFPA 20, 6.2.1, 6.2.2, ] Power Wiring. Power circuits and wiring methods shall comply with the requirements in 695.6(A) through (G), and as permitted in (A), Exception No. 4; , Exception No. 4; , Exception No. 2; ; ; 240.4(A); and A. Service Conductors. Supply conductors shall be physically routed outside a building(s) and shall be installed as service entrance conductors in accordance with Article 230. Where supply conductors cannot be physically routed outside buildings, they shall be permitted to be routed through building where installed in accordance with 230.6(1) or (2). Where a fire pump is wired under the provisions of 695.3(B)(2), this requirement shall apply to all supply conductors on the load side of the service disconnecting means that constitute the normal source of supply to that fire pump. ~ 1 ~

3 Exception: Where there are multiple sources of supply with means for automatic connection from one source to the other, the requirement shall only apply to those conductors on the load side of that point of automatic connection between sources. B. Circuit Conductors. Fire pump supply conductors on the load side of the final disconnecting means and overcurrent device(s) permitted by 695.4(B) shall be kept entirely independent of all other wiring. They shall only supply loads that are directly associated with the fire pump system, and they shall be protected to resist potential damage by fire, structural fire, or operational accident. They shall be permitted to be routed through a building(s) using one of the following methods: 1. Be encased in a minimum 50 mm (2 in.) of concrete 2. Be within an enclosed construction dedicated to the fire pump circuit(s) and having a minimum of a 1-hour fire resistive rating 3. Be a listed electrical circuit protective system with a minimum 1-hour fire rating Exception: the supply conductors located in the electrical equipment room where they originate and in the fire pump room shall not be required to have the minimum 1-hour fire separation or fire resistance rating, unless otherwise required by 700.9(D) of this Code. C. Conductor Size. 1. Fire Pump Motors and Other Equipment. Conductors supplying a fire pump motor(s), pressure maintenance pumps, and associated fire pump accessory equipment shall have a rating not less than 120 percent of the sum of the fire pump motor(s) and pressure maintenance motor(s) full-load current(s), and 100 percent of the associated fire pump accessory equipment. 2. Fire Pump Motors Only. Conductors supplying only a fire pump motor(s) shall have a rating not less than 120 percent of the fire pump motor(s) full-load current(s). D. Overload Protection. Power circuits shall not have automatic protection against overloads. Except as provided in 695.5(C)(2), branch-circuit and feeder conductors shall be protected against short circuit only. Where a tap is made to supply a fire pump, and the tap wiring is run in accordance with 230.6, the applicable distance and size restriction in shall not apply. Exception No. 1: Conductors between storage batteries and the engine shall not require overcurrent protection or disconnecting means. Exception No. 2: For on-site standby generator(s) that produce continuous currents in excess of 225 percent of the full-load amperes of the fire pump motor, the conductors between the on-site generator(s) and the combination fire pump transfer switch controller or separately mounted transfer switch shall be installed in accordace with 695.6(B) or protected in accordance with The protection provided shall be in accordance with the short-circuit current rating of the combination fire pump transfer switch controller or separately mounted transfer switch. E. Pump Wiring. All wiring from the controllers to the pump motors shall be in rigid metal conduit, intermediate metal conduit, liquidtight flexible metal conduit, or liquidtight flexible nonmetallic Type LFNC-B, or Type MI cable. F. Junction Points. Where wire connectors are used in the fire pump circuit, the connectors shall be listed. A fire pump controller or fire pump power transfer switch, where provided, shall not be used as a junction box to supply other equipment, including a pressure maintenance (jockey) pump(s). A fire pump controller and fire pump power transfer switch, where provided, shall not serve any load other than the fire pump for which it is intended. ~ 2 ~

4 NEC 695.6B NEC NEC G. Mechanical Protection. All wiring from engine controllers and batteries shall be protected against physical damage and shall be installed in accordance with the controller and engine manufacturer s instructions. B. Circuit Conductors. Fire pump supply conductors on the load side of the final disconnecting means and overcurrent device(s) permitted by 695.4(B) shall be kept entirely independent of all other wiring. They shall only supply loads that are directly associated with the fire pump system, and they shall be protected to resist potential damage by fire, structural fire, or operational accident. They shall be permitted to be routed through a building(s) using one of the following methods: 1. Be encased in a minimum 50 mm (2 in.) of concrete 2. Be within an enclosed construction dedicated to the fire pump circuit(s) and having a minimum of a 1-hour fire resistive rating 3. Be a listed electrical circuit protective system with a minimum 1-hour fire rating Exception: the supply conductors located in the electrical equipment room where they originate and in the fire pump room shall not be required to have the minimum 1-hour fire separation or fire resistance rating, unless otherwise required by 700.9(D) of this Code. Equipment Location. A. Controllers and Transfer Switches. Electric motor-driven fire pump controllers and power transfer switches shall be located as close as practicable to the motors that they control and shall be within sight of the motors. B. Engine-Drive Controllers. Engine-drive fire pump controllers shall be located as close as is practical to the engines that they control and shall be within sight of the engines. C. Storage Batteries. Storage batteries for diesel engine drives shall be rack supported above the floor, secured against displacement, and located where they will not be subject to physical damage, flooding with water, excessive temperature or excessive vibration. D. Energized Equipment. All energized equipment parts shall be located at least 300 mm (12 in.) above the floor level. E. Protection Against Pump Water. Fire pump controllers and power transfer switches shall be located or protected so that they will not be damaged by water escaping from pumps or pump connections. F. Mounting. All fire pump control equipment shall be mounted in a substantial manner on noncombustible supporting structures. Control Wiring. A. Control Circuit Failures. External control circuits that extend outside the fire pump room shall be arranged so that failure of any external circuit (open or short circuit) shall not prevent the operation of a pump(s) from all other internal or external means. Breakage, disconnecting, shorting of the wires, or loss of power to these circuits could cause continuous running of the fire pump but shall not prevent the controller(s) from starting the fire pump(s) due to causes other than these external control circuits. All control conductors with the fire pump room that are not fault tolerant shall be protected against physical damage. [NFPA 20, ] B. Sensor Functioning. No undervoltage, phase-loss, frequency-sensitive, or other sensor(s) shall be installed that automatically or manually prohibit actuation of the motor contactor. [NFPA 20, ] Exception: A phase loss sensor(s) shall be permitted only as a part of a listed fire pump controller. C. Remote Device(s). No remote device(s) shall be installed that will prevent automatic operation of the transfer switch. [NFPA 10, ] D. Engine-Drive Control Wiring. All wiring between the controller and the diesel engine ~ 3 ~

5 NEC NEC 700.9D shall be stranded and sized to continuously carry the charging or control currents as required by the controller manufacturer. Such wiring shall be protected against physical damage. Controller manufacturer s specifications for distance and wire size shall be followed. [NFPA 20, ] E. Electric Fire Pump Control Wiring Methods. All electric motor-driven fire pump control wiring shall be in rigid metal conduit, intermediate metal conduit, liquidtight flexible metal conduit Type B (LFNC-B), or Type MI cable. F. Generator Control Wiring Methods. Control conductors installed between the fire pump power transfer switch and the standby generator supplying the fire pump during normal power loss shall be kept entirely independent of all other wiring. They shall be permitted to be routed through a building(s) encased in 50 mm (2 in.) of concrete or within enclosed construction dedicated to the fire pump circuits and having a minimum 1-hour fire resistance rating, or circuit protective systems with a minimum of 1-hour fire resistance. The installation shall comply with any restrictions provided in the listing of the electrical circuit protective system used. Transfer Equipment. A. General. Transfer equipment, including automatic transfer switches, shall be automatic identified for emergency use, and approved by the authority having jurisdiction. Transfer equipment shall be designed and installed to prevent the inadvertent interconnection of normal and emergency sources of supply in any operation of the transfer equipment. Transfer equipment and electric power production systems installed to permit operations in parallel with the normal source shall meet the requirements of Article 705. B. Bypass Isolation Switches. Means shall be permitted to bypass and isolate the transfer equipment. Where bypass isolation switches are used, inadvertent parallel operations shall be avoided. C. Automatic Transfer Switches. Automatic transfer switches shall be electrically operated and mechanically held. D. Use. Transfer equipment shall supply only emergency loads. E. Fire Protection. Emergency systems shall meet the following additional requirements in assembly occupancies for not less than 1000 persons or in buildings above 23 m (75 ft.) in height with any of the following occupancy classes: assembly, educational, residential, detention and correctional, business, and mercantile. 1. Feeder-Circuit Wiring. Feeder-circuit wiring shall meet one of the following conditions: i. Be installed with buildings that are fully protected by an improved automatic fire suppression system. ii. Be a listed electrical circuit protective system with a minimum 1-hour fire rating iii. Be protected by a listed thermal barrier system for electrical system components iv. Be protected by a fire-rated assembly listed to achieve a minimum fire rating of a 1 hour v. Be embedded in not less than 50 mm (2 in.) of concrete vi. Be a cable listed to maintain circuit integrity for not less than 1 hour when installed in accordance with the listing requirements Building/dubiel/fire pump wiring code ~ 4 ~